Mobile batching plant



5 Sheets-Sheet 1 A. R. ROSS ET AL MOBILE BATGHING PLANT Jan. 3, 1967 Filed Feb. 12, 1965 Jan. 3, 1967 A. R. Ross ET AL 3,295,698

MOBILE BATCHING PLANT Filed Feb. l2. 1965 3 Sheets-Sheet 2 OMON.

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Jan. 3, 1967 Filed Feb. l2, 1965 FIGB.

A. R. ROSS ET AL MOBILE BATCHING PLANT 3 Sheets-Sheet 5 United States Patent O 3,295,698 MOBILE BATCHING PLANT Arnold R. Ross, Lakeland, Fla., and Charles Schroedl,

Milwaukee, and Robert W. Strehlow, New Berlin, Wis.,

assignors to Rex Chainbelt Inc., Milwaukee, Wis., a

corporation of Wisconsin Filed Feb. 12, 1965, Ser. No. 432,205 7 Claims. (Cl. 214-2) This invention relates, generally, to hatching plants for apportioning the ingredients of concrete or the like and m-ore particularly to an improved mobile Ihatching plant of large capacity adapted for transportation along a highway as a single unitary vehicle.

In the preparation of freshly mixed concrete for construction work, such as in laying slabs for highways for example, it is desirable that the various ingredients ernployed in the mix to be apportioned expeditiously and with a high degree of exactness to insure that the resulting concrete structure will he of the required strength and have other suitable characteristics. In order to insure the proper proportioning of the ingredients for concrete that is being mixed in considerable quantities, large and expensive stationary hat'ching pl-ants generally are employed wherever concrete construction activities are in progress. Such plants are required to Ihe provided with precise and complicated automatic apportioning and dispensing apparatus whereby the proper port-ions of cement, sand, and other aggregates are weighed out, sometimes with the required quantity -of water together with its additives, to form batches of appropriate sizes for mixing in concrete mixes of various types being served.

Because of the complexity and expensive natu-re of these large, permanently installed hatching plants, it is an economic necessity that they operate -at high capacity in` order that the overhead expense involved may he spread over a large volume of concrete products. It `follows then that to justify the use of a large permanent automatic hatching plant it has to he located in an area where extensive concrete construction work is being carried on continuously 4and in considerable volume. Ingredients hatched in a plant of this nature are delivered to the site of placement by hauling vehicles of various types, and the cost of the finished concrete depends upon the distance over which the hatched material must he transported. Obviously, there is a limit at which it is no longer economically feasible to transport the ingredients of concrete from a distant central hatching plant.

In regions where the normal use of freshly mixed concrete does not justify the maintenance of a large permanent automatic stationary hatching plant and where a single relatively large construction project such as a new highway, an airport or 4the like is undertaken, it is customary to erect a portable hatching plant. Such a plant is usually quite large and is ordinarily transported from one to another site as several separate units. The work of erecting and interconnecting these several units into a unitary hatching establishment is time consuming and expensive and at the con-clusion of the construction project, it likewise is expensive to take down the plant and move the separated units to a new site.

It is accordingly a general object of the present invention to provide an improved mobile concrete hatching plant of high capacity that is movable as a single highway unit.

Another object of the present invention is to provide a mobile hatching plant that is mounted as an integral unit on a single vehicle of dimensions appropriate for travelling on public highways.

Another object is to provide a mobile hatching plant having movable elements that may be folded into the ICC vehicle frame for transportation and then may be easily and quickly erected to their operating positions by power.

Another object is to provide a mobile hatching plant of dimensions suitable -for transportation as a single unit on highways while having large capacity for -receiving and apportioning ingredients in effecting major hatching operations.

A further object is .to provide a mobile hatching plant that is arranged to he self-erecting into operating position readily and quickly without the use of a lifting crane or other auxiliary equipment.

According to the present invention, a complete hatching plant suitable for expeditiously apportioning the ingredients of concrete is mounted as a unitary integral structure in a single vehicle of dimensions suitable for operating on public highways. This improved mobile hatching plant includes both aggregate hatching equipment and cement hatching equipment, and is arranged to operate at relatively large capacity in delivering successive hatches of apportioned ingredients for concrete. The vehicle carrying the unitary mobile hatching plant is in the form of a semi-trailer provided at one end with supporting road Wheels and at the other end with a gooseneck fifth wheel arrangement for engagement by a towing tractor. The vehicle frame is of open box construction for receiving the movable parts of the hatching apparatus when it is folded inward for transportation. A belt conveyor arranged along the bottom of the frame is pivoted upward when positioned for transporting hatched aggregates and cement to an elevated charging head extending from one end of the plant for discharging the ingredients into a stationary mixer, a transit mixer, or some other hauling vehicle as the situation may require. The conveyor structure is so mounted that its upwardly extending discharge end may -be lowered to a position just above the cab of the towing tractor when the ,apparatus is being transported. In order to provide adequate capacity for furnishing batches of concrete ingredients continuously at a rapid rate, the mobile bat-ching plant is equipped with a cement hin of relatively large size. With the conveyor in lowered position, the cement bin may he pivoted downwardly into the vehicle frame with the lower surface of the bin conforming generally to the shape of the lowered conveyor. The movable cement hin is piv-otally supported at its discharge end on the upper part of the vehicle frame in such manner that it may he pivoted upwardly and rearwardly out of the frame to a vertical operating position. The conveyor is then lifted into the space previously occupied by the cement bin thereby elevating its projecting discharge end. With the cement bin in raised position, cement may flow by gravity into a batcher which discharges the hatched cement on to the conveyor. An aggregate bin carried in the frame rearwardly of the cement bin is divided into three compartments holding respectively sand and two sizes of stone. The aggregates may he discharged hy gravity into an aggregate batcher which discharges successive batches on to the conveyor. As the hatched aggregates are carried forward hy the conveyor belt the -cement batcher discharges the hatched cement on top of the aggregates, the -comhined batch being then carried outward and upward to the discharge end of the conveyor. The aggregate batcher and the cement batcher both are controlled hy interlocking automatic control apparatus comparable to the lcontr-01s used on stationary hatching plants whereby accurately sized and proportioned hatches of ingredients may be discharged successively at a rate substantially equal to the production rate of the usual large stationary hatching pl-ant. When moving the mobile hatching plant to another site, the charging conveyor is lowered Within the vehi-cle frame after which the cement bin is pivoted forwardly and downwardly into the frame above the conveyor. The towing tractor is then connected to the fth wheel whereupon the entire mobile batching equipment may be moved along the highway as a single unit in the manner of the usual semi-trailer road vehicle.

The foregoing and other objects will become more fully apparent as the following detailed description of the improved mobile batching plant is perused in conjunction with its representation in the -accompanying drawings illustrative of the invention in its presently preferred form, wherein:

FIGURE l is a view in left side elevation of a tractordrawn mobile batching plant embodying the invention, parts of the plant having been removed to show the bin and conveyor lowered .to their folded transporting positions. The towing tractor is shown in outline; the conveyor is shown diagrammatically;

FIG. 2 is a view similar to FIGURE 1 with the conveyor and bin of the plant raised to their operating positions and with some parts broken away to show the pivotal support of the conveyor;

FIG. 3 is a plan view of the mobile hatching plant l shown in FIG. 2;

FIG. 4 is a view similar to FIG. 2 with other parts broken away;

FIG. 5 is a view in verti-cal transverse section through the hatching plant taken on the plane represented by the lines 5 5 of FIG. 2;

FIG. 6 is an enlarged view in vertical transverse section similar to the lower part of FIG. 5 and showing the cement discharging arrangement;

FIG. 7 is an enlarged fragmentary detailed view taken on the plane represented by the lines 7 7 in FIG. 2 and showing a cement bin locking pin; and

FIG. 8 is an enlarged fragmentary detailed view taken 0n the plane represented by the lines 8 8 in FIG. 2 and showing one of the two cement bin supporting trunnions.

. The chassis of trailer 9 comprises essentially a Ibox-like hollow truss frame 10 that is supported at the rear on a pneumatic tired four wheeled bogie truck 11. At its forward end, the frame 10 is provided with a narrowed and raised goose-neck element 12 that carries a king pin or fifth wheel arrangement 13 by means of which the forward end of the mobile plant may be supported upon and carried by a towing tractor truck T to constitute therewith the usual semitrailer and tractor combination road vehicle.

As appears in the drawings, the box-like frame 10 of the vehicle includes a pair of spaced parallel longitudinally disposed lower side frame members 15 that are interconnected by several transverse or cross members 16 to constitute a base structure comparable to the truck frame of the usual ilat bed vehicle. Spaced vertical frame members 17 extending upward from the lower side frame memlbers 15 support a pair of upper spaced parallel longitudinally disposed side frame members 18 that complete the double truss structure yforming the open box-like fr-ame 10 of the vehicle.

The box frame structure 10 is preferably formed primarily of bent steel plates reinforced by standard structural elements to c-onstitute a fabricated truss of suitable shape and having sufficient strength and rigidity to support the heavy loads imposed by the hatching equipment and the kconsiderable quantities of heavy ingredients contained therein while a hatching operation is in progress. The running gear 11 at the trailing end of the frame 10, is constituted by a pair of spring mounted axles 21 each of which carries dual wheels 22 mounted on its respective ends and provided with the usual pneumatic tires. The several wheels 22 are, of course, provided with brakes that are operated from the towing tractor T and the usual tail lights (not shown), likewise operated from the tractor, are mounted on the back of the frame 10. In setting up batching plant lfor operation, the frame 10 is blocked up securely Aupon blocks B, as shown in FIGS. 2, 4 and 5, whereupon the towing tractor T is unhitched and moved away.

As best shown in FIGS. l, 2 and 4, the large capacity ingredient hatching equipment carried within the box frame 10 of the mobile vehicle includes, in general, a weighing aggregate hopper or batcher 25 of usual construction that is mounted in the rear part of the vehicle frame 10 directly below a compartmented aggregate bin 26 that feeds by gravity into the batcher 25. Just forwardly of the aggregate batcher 25 and centrally of the vehicle, a weighing cement batcher or hopper 27 is secured in the frame 10. The cement batcher 27 is disnosed below and is fed by gravity from the large movable cement bin 28 that is pivotally supported on and between the spaced upper side frame members 18 in such a manner that it may be pivoted or swing from an upright operating position as shown in FIGS. 2 and 4, to a horizon-l tal travelling position as indicated in FIGURE 1 of the drawing.

Beneath the aggregate batcher 2S and the cement batcher 27 a belt conveyor structure 3l) extends longitudinally along the center of the frame 10 in position to receive and to transport batches Iof material discharged on to it from the respective batchers 25 and 27 .j As best shown in FIGS. l, 2 and 4, the conveyor 30 extends forwardly within and along the bottom of the frame 10 beneath the two batchers and then upwardly to project outwardly at the forward end of the frame in an elevated position adapted to charge hatched ingredients into a mixer or a hauling vehicle such as is represented in FIG. 2 by a charging hopper H of a truck mixer or the like.

The conveyor structure 30 is pivotally mounted in the rear part of the frame 10 on the axis of a horizontal pivot 31 disposed beneath theaggregate batcher 25. When the cement bin 28 is in the upright operating position shown in FIGS. 2 and 4, the conveyor 30 is likewise pivoted upward to its raised operating position, as shown. When the apparatus is to be moved to a new location, the conveyor 30 is pivoted downward to the transporting position and the cement bin 28 is then likewise pivoted downward to repose just above the lowered conveyor structure 30 with the forward end of the conveyor then projecting just above the cab of the towing tractor T, as shown in FIGURE 1.

As best shown in FIGS. 2, 3 and 4, the xed aggregate bin 26 is of generally rectangular shape and is fitted between and supported yby the spaced upper side frame members 18 at the trailing end of the frame 10. In this way the aggregate bin 26 consitutes an interconnecting or reinforcing element securing together the rearward ends of the upper side frame members 18 thereby forming a transverse brace for the truss structure that constitutes the rear cross connection of the frame 10. The four vertical frame members 17 that are disposed at the rej spective corners of the aggregate bin 26 support the weight of the bin and its contents upon the lower side members 15 of the frame that are in turn supported by the blocks B resting upon the ground.

A transverse partition 34 within the aggregate bin 26 isolates the rear third of the bin, as best shown in FIG. 3 to constitute a separate rear compartment 35 that extends across and is adapted to be loaded from the rear of the hatching plant. A central longitudinal partition 36 extends forwardly from the transverse partition 34 and divides the remaining two-thirds of the bin into two lengthwise side compartments 37 and 38 that are adapted to be loaded with aggregate material from the respective sides of the hatching plant.

The height of the outer sidewalls of the aggregate bin may be reduced at the three loading positions if necessary in order to facilitate loading the compartments by means of a front end or scoop type loader or the like, not shown. The front end loader may be used to transfer the aggregates more or less continuously from nearby storage piles into the respective compartments of the agof portable conveyors in which case the capacity of the compartments may be increased somewhat by providing removable side plate extensions, not shown, that t in and close the loading position openings to make the compartment walls higher.

Ordinarily the three bin compartments are used respectively to store sand, small stones or gravel and large stones, that make up the aggregate batches. In the particular plant shown in the drawing, the aggregate bin 26 has a total capacity of about twenty cubic yards of material which weighs about thirty tons. Although the capacity of the bin 28 is rather limited, when the batching plant is in full operation, aggregate materials from the nearby stock piles are fed into the bin compartments as fast as needed to keep them lled. The bottom of each compartment of the aggregate bin 26 is provided with two of the usual clamshell batching gates 39 that are air operated and automatically controlled electrically from the batching hopper scales.

The aggregate Ibatcher 25 is of the cumulative type and includes the usual hopper and the weighing scale that operates to control the batching gates 39 of the three aggregate compartments successively in well known manner to Weigh out batches of each aggregate one after the -other in order that the proper amount of each material may be received in the hopper from the respective compartments. The different materials are fed through the gates 39 by gravity sequentially into the hopper of the aggregate batcher 25 under the control of batch weighing apparatus that operates in conjunction with a batching control panel 40 mounted at the forward end of the plant on the left side as shown in FIG. 2. During batching the weight of the material reposing in the hopper of the batcher 25 is indicated continuously on an aggregate dial scale 41 mounted in the left side of the frame near the aggregate batcher 25 and in position to be viewed by the plant operator from his station before the control panel 40.

After all of the three aggregates have been weighed into the aggregate batcher 25 in the desired amounts, the combined batches of material are discharged automatically on to a moving belt 42 of the belt conveyor 30 at the appropriate time under control of the control apparatus associated with the control panel 40 through opening of a plurality of air operated clamshell discharge gates 44 in the bottom of the aggregate batcher 25. Preferably, these discharge gates 44 are adjustable and are arranged to be opened to an adjusted, partially open position or stage and then to a fully opened position to control the flow in a manner to distribute the batched material over a considerable length of the travelling belt 42 of the belt conveyor 30 thereby intermingling and premixing the ingredients as the belt advances longitudinally along the bottom of the frame 10.

The cement weighing batcher 27 is likewise of well known construction and is arranged to receive cement that flows down by gravity from the large cement bin 28 when the bin is in the upright operating position shown in FIGS. 2 and 4. The flow of cement from the bin 28 into the hopper of the cement batcher 27 is controlled by a batching gate 45 in the tapered lower end of the cement bin. This batching gate 45 is of the air operated and electrically controlled rotary type and is actuated by control apparatus associated with the control panel 40 which is responsive to the amount of the cement in the hopper of the weighing batcher 27. The weight of the cement in the batcher 27 is shown continuously on a cement scale dial 46 that is disposed on the left side of the plant adjacent to the control panel 40 where it may be observed readily by the plant operator.

Fully automatic control of the cement weighing operation is effected in a well known manner by the control apparatus of the control panel 40 which is inter-connected with and operates in conjunction with the control system for the aggregate batcher 25. As is Well known, the pro- 6 portions of the various aggregates and cement in a batch and the size of the total batch may be established in advance by the plant operator through adjustment of the batching controls on the control panel 40.

After a full batch of cement has been weighed out in the hopper of the cement batcher 27 the cement is discharged at the appropriate time under automatic control and distributed along the top of the batch of aggregates being carried forward on the belt 42 of the conveyor 30. For this purpose a cement discharging rotary gate 47 in the bottom of the cement batcher opens gradually under automatic control in a manner to spread the cement evenly over the batched aggregates moving forward on the conveyor belt 42. From the cement batcher rotary discharge gate 47, the cement flows into a blender box 48 that fits over and encloses a segment of the belt conveyor 30 and that is provided with depending side skirts 49 that extend rearwardly along the conveyor. As best shown in FIG. 6, the side skirts 49 extend down to and engage the respective outer edge portions of the conveyor belt 42 in manner to confine the cement and prevent it from overflowing at the sides of the belt and also to 4prevent the escape of cement dust.

In this way the cement is caused to spread over the top of the aggregates already on the conveyor belt in a manner to provide for intermixing of the cement and the aggregates to better prepare the combined batch of material for charging into a hauling vehicle. As previously indicated, by appropriate adjustment of the control system through manipulation of controls on the operators panel 40 in a well known manner, this entire batching operation is accomplished automatically in accordance with the preestablished requirements as to proportions of ingredients and the sizes of the individual batches that are necessary for a particular concrete mixing operation being served.

In the exemplary batching plant apparatus set forth herein, each of the two batchers 25 and 27 is designated as being of four yard size that is, they each are rated as having the capacity for batching the ingredients required for making four cubic yards of concrete in a full batch. The control equipment associated with the batchers and the control panel 40, however, is arranged to be regulated in a well known manner to produce batches of fractional sizes and is ordinarily adjustable by increments of onequarter cubic yard. Furthermore, the control system used in this plant is capable of recycling or repeating automatically when desired to provide double batches selectively if batches in amounts larger than four cubic yards are specified. By this arrangement, the individual batches automatically produced may be of any desired size selected by one-quarter yard increments up to a maximum of eight cubic yards, as may be required to charge various truck mixers, for example, of different specic capacities within this range. Other weighing sequences may, of course, be employed where desirable.

The relatively large cement bin 28 is of sucient capacity to contain an adequate supply of cement for making a considerable amount of concrete thereby insuring continuous operation of the batching plant at a high rate of production. In the particular batching plant set forth herein, the cement bin 28 has a capacity of somewhat over three hundred barrels of bulk dry cement which is the equivalent of about three truck loads of the size ordinarily delivered by the usual bulk cement transporting vehicle.

The rate at which successive complete batches of material may be weighed out in this mobile plant and delivered to waiting transportation vehicles is dependent largely upon the capacity of the belt conveyor 30 in moving the material from the batchers to the receiving vehicle. By using a belt 42 of say forty-eight inches in width and operating it at high speed, it is possible with the apparatus shown to produce as much as six hundred cubic yards of batched ingredients in an hour. v This rate of production can be maintained as long as adequate supplies of cement and aggregate materials are delivered to the mobile hatching plant and trucks are available in sufiicient numbers to haul away the product. This output compares favorably with the production capacity of the usual stationary hatching plant that is provided with large material storage facilities.

If lower rates of production are adequate for the work at hand, a narrower and slightly slower conveyor 30 may he used in the hatching plant. In the particular machine illustrated, the belt 42 of the conveyor may he of any selected size between twenty-four inches and forty-eight inches in width. Likewise the speed may vary from three hundred fifty feet per minute to ve hundred and fifty feet per minute, for example. In this manner the capacity of the mobile hatching plant may be established at from one hundred forty to six hundred cubic yards of concrete ingredients an hour as may be required.

The cement bin 28 is provided with the usual accessories such as aeration pads, vents, indicators, and a pipe for receiving bulk cement delivered by air flow from a hulk cement transportation vehicle. As best shown in FIG. 4, the cement hatching gate 45 is of the rotary type and is mounted in the bottom of a reduced offset pyramidal discharge outlet portion of the cement hin 28. When the hin 28 is in vertical operating position, the outlet of the rotary gate 45 is connected to the top of cement hatcher 27 by means of the exible tube 51 arranged to he readily clamped to communicate with hatcher 27.

As previously indicated, the cement hin 28 is pivotally mounted in the vehicle frame 10 midway of its length for pivotal movement between the vertical operating position shown in FIGS. 2 and 4 and the horizontal transporting .position shown in FIGURE 1. In order that the cement bin hatching gate 45 may be supported high enough in the frame 10 to discharge into the cement hatcher 27 when the bin is in vertical position, the pivot axis of the hin is located at an elevated position on the frame 10 and close to the gate 45. To provide for this arrangement, the lower part or discharge end of the vertical bin is tapered in an offset manner to position the hatching gate 45 off center and approximately in vertical alignment with the rear wall of the hin.

When the bin is lowered to its travelling position as shown in FIGURE l, it ts down between the upper side frame members 18 in such manner that the hatching gate 45 is substantially in line with the respective upper side .frame members 18. By arranging the pivot axis through 'the upper side frame members in this elevated position -and close to the gate 45, the gate remains in the region of the upper side frame members when the bin is pivoted upward thereby providing sufficient room between the gate 45 and the conveyor 30 for accommodating the cetapered end of the bin so auxiliary structure is provided for securing the pivots to the cement bin. As best shown in FIG. 5,I this auxiliary supporting structure includes two large rectangular vertically positioned plates 52 that are approximately in line with the right and left sides of the bin 28, respectively, and that in effect constitute downward extensions of the hin sides which fit inside of the upper side frame members 18. Each of the plates 52 carries an outwardly projecting pivot or trunnion 53, the two trunnions defining the pivot axis in the region of the hatching gate 45. The trunnions 53 are rotatably received or journalled in bearings 54 mounted in the respective upper side frame members 18 as more clearly shown enlarged in FIG. 8.

Since the trunnions 53 as well as the hatching gate 45 are positioned toward the trailing side of the hin 28 when in its vertical position as shown in FIG. 2, the trunnions are disposed eccentrically with regard to the center of gravity of the bin and its load of cement. To maintain the bin in its vertical position and to balance and distribute the load on the frame 10, the rectangular extension plates 52 are provided near their forward edges with bin supporting locking arrangements including round holes 57 that align with similar holes 58 in the upper side frame members 18, respectively. When the bin 28 is in its vertical position, removable locking pins 59 are passed through the aligned holes 57 and 58 on each side of the frame 10, as best shown enlarged in FIG. 7, to lock the plates 52 securely to the frame members 18.

The two locking pins 59 are of approximately the same size and strength as the trunnions 53 and are so positioned that the weight of the bin is divided more or less equally between the pins and the trunnions. In this manner the balanced load imposed by the bin 28 is transmitted through the pins and trunnions onto the side frame members 18 at longitudinally spaced positions near the midlength of each beam. The distributed weight is largely carried hy the adjacent four vertical frame members 17 which in turn transfer the load to the lower side frame members 15. As shown in FIG. 2, the load imposed in this manner by the hin 28 on the frame structure 10 is well distributed over the hlocks B that are placed on the ground under the side frame members 15 when the plant is blocked up in operating position.

When the cement hin 28 is to be lowered to its travelling position, the two locking pin 59 are withdrawn and the bin is pivoted forwardly and downwardly between the upper side frame members 18 in such manner that its ilat gate carrying rearward side then becomes the top surface and is disposed substantially flush with the side frame members 18 with the hatching gate 45 positioned between the two upper frame members. Abutment strips 61 in the form of channel members secured on the respective right and left sides of the rear edge of the hin engage the upper side frame members 18 as shown in FIGURE 1 to support the bin when lowered to its horizontal travelling position.

When in this lowered position, the top of the Ihin does not project above the highest part of the side frame members 18 and therefore the hin in its travelling position does not increase the over-all height of the vehicle as established by the frame 10 and therefore does not interfere with movement under bridges and the like. With the cement hin in its lowered position, its forward face becomes its lower side and lies close to and is shaped to conform generally to the shape of the underlying upwardly `sloping belt conveyor structure 30 which is also then in its lowered travelling position. Likewise, the forward end of the lowered cement bin 28 is tapered inwardly or narrowed transversely, as shown in FIG. 3, in order to conform to the inwardly sloping side walls of the narrowed forwardly projecting goose neck 12 at the front end of the frame 10.

The two upper corners at the forward end of the reposing cement hin in travelling position, are provided with crane hook eyelets 62 that may be used if necessary under some unusual circumstances to lift the hin to its operating position by means of a travelling crane or the like. Ordinarily, however, the mobile hatching plant is selferecting thereby obviating the need for a crane or other supplemental equipment when the plant is being prepared for operation after being moved to a new location.

To this end, there is incorporated within the unitary mobile hatching apparatus, a yhydraulically actuated lifting device 63 in the form of a multiple stage telescopic hydraulic cylinder. As appears in FIGS. 2 and 3, the lower closed end of the multistage cylinder 63 is pivotally connected to one of the lower frame cross members 16 in an offset position at the left side of the conveyor structure 30. The upper end of the hydraulic actuator 63 is pivotally and detachahly connected to a lug 64 on the forward side of the cement hin 28. When hydraulic pressure iluid is admitted to the lower end of the cylinder 63 the actuator is extended as shown in FIG. 2, to tilt the cement bin from its horizontal travelling position to its upright operating position.

Hydraulic uid under pressure for extending the lifting actuator 63 and for other purposes is furnished by a hydraulic supply unit 67 that is mounted in the frame 10 near the operators station, as appears in FIG. 2. The hydraulic supply unit 67 includes the usual tank for hydraulic fluid together with motor driven pumps and control valves, not shown, by means of which hydraulic pressure may be applied to or released from the bin lifting actuator 63 selectively by the plant operator in pivoting the cement bin 28 between its travelling and its operating positions. When the cement bin 28 is raised from the horizontal transportation position to the vertical upright position to the vertical upright position by operation of the actuator 163, the holes 57 and 58 are brought into alignment and the locking pins 59 are inserted in the aligned holes as shown in FIG. 7 to lock the bin in raised position as previously explained.

With the Ibin thus balanced and locked in its vertical operating position, the quick clamp connector 51 is engaged to connect the cement bin outlet hatching gate 45 to the cement batcher 27. Since the hydraulic actuator 63 is not required to maintain the cement bin in elevated position after the locking pins 59 are inserted, it is preferable to disconnect its upper end from the lug 64 in order that it may be retracted or collapsed, as shown in FIG. 4, to protect the seals and surfaces of its telescoping parts from rust and cement dust.

With the cement bin 28 raised to its vertical operating position, the conveyor structure 30 may be pivoted upward about its pivot pin 31 in such manner that its forward portion moves upward within the frame 10 into the space vacated by the cement bin in tilting to its upright position. This raises the forwardly projecting head end of the conveyor 30 to an elevated positi-on higher than the vehicle frame 10 and that is better adapted for charging hatched ingredients from the belt 42 into a receiving transportation vehicle such as is indicated in FIG, 2 by the truckmixer charging hopper H.

The conveyor structure 30 includes a framework made up primarily of spaced side frame members 70 that are constituted by inwardly facing channel elements connected together in spaced relationship by transverse members 71 as shown in FIG. 6 to form a strong rigid frame structure that is self-supporting and that pivots as a unit upon the conveyor pivot pin 31 at the rear of the vehicle frame 10.

Upward pivoting of the conveyor structure 30 is accomplished by a pair of hydraulic actuators 73 mounted on the forwardly projecting goose-neck 12, the -actuators being pivotally connected at their upper ends to the lower flanges of the respective conveyor side frame channel members 70. As shown in FIGS. 1 and 4, the hydraulic actuators 73 are -similarly pivotally connected to and sup.- ported at their lower ends upon the respective sides of the forwardly projecting goose-neck portion 12 of the vehicle frame 10. The hydraulic actuators 73 are supplied with hydraulic Huid under pressure from the previously mentioned hydraulic supply unit 67 in a well known manner. To this end, the hydraulic supply unit is provided with suitable additional control valves and associated control apparatus (not shown) whereby the hydraulic units 73 may be actuated selectively to raise or lower the conveyor structure 30 as required.

As may be seen in the drawing, the forward end of the vehicle frame 10 is provided with an upwardly and forwardly projecting extension 75 of light structural members that serves to support the projecting forward end of the conveyor structure 30 in either -of its two positions. As best shown in FIGURE 1, the frame extension 75 carries at its outer end a cross piece 76 that Iis positioned to be engaged by and support the side frame members 70 near the outer end of the conveyor 3() when the conveyor structure is in its lowered or traveling position. When the conveyor 30 is raised to its upward operating position shown in FIGS. 2 and 4, locking pins 77 are inserted in aligned openings to lock the conveyor to an upwardly extending forward portion 78 of the frame extension 75. In this manner, during a hatching operation, the projecting forward end of the conveyor 30 with the load imposed thereon by the batches of ingredients being conveyed for charging into a transportation vehicle, is supported securely by the forwardly projecting frame extension 75.

As best shown in FIGS. l and 4, the channel side frame members 70 of the conveyor structure 30 carry a series of spaced troughing rollers 79 that support the conveyor belt 42 in a well known manner best adapted to convey the b-atched material forward and upward for charging into a waiting vehicle. At its projecting discharge end, the conveyor is yprovided with the usual head pulley 81 over which the belt 42 operates in a manner to discharge its load of ingredients into a discharge chute 8-2 that is arranged to guide the down-flowing stream of the several ingredients into a transporting vehicle such as the truckmixer, for example, represented by the charging hopper H shown in FIG. 2. Since both the hatched aggregates and the cement are stratified and spread on the conveyor belt 42 over a considerable length thereof, the ingredients of each complete batch are charged into the vehicle together in such manner that the various ingredients are intermingled and premixed to a considerable extent before the actual mixing operation begins in the receiving concrete lmixer.

After the belt 42 passes over the head pulley 81, its returning lower run is supported by straight return rollers S4 that are spaced along the lower side of the channel frame members 70 somewhat farther apart than the load carrying troughing rollers 79 and that operate in a manner to support the belt 42 in flat condition as shown in FIG. 6.

Although the head pulley 81 may, if desired, be driven in the usual manner, generally it has -been found to be more convenient to drive the conveyor belt 42 at a position within the main frame 10 of the hatching plant, as shown in FIGS. l and 4. To accomplish this, the lower or returning run of the belt 42 is looped around a take-up pulley 86 that is movably mounted in brackets suspended below the conveyor side frames 70 in manner to be adjustable longitudinally of the side frames for tightening the belt. From the take-up pulley 86 the belt 42 is doubled back :and looped around a driving pulley 87 from which it extends rearwardly again over additional return rollers 84.

The driving pulley 87 is driven by a speed reducing mechanism 38 that is pivotally suspended beneath the conveyor side frames 70. The speed reducer88- is provided with a driving sheave 89 which is connected by multiple V belts '90 to a similar sheave 91 on a driving motor 92 that is mounted on a bracket 93 attached to the main frame 1t) of the vehicle. When the conveyor 3-3 is in its raised or operating position, the speed reducer 88 is pivoted upward by means of a turnbuckle 94 to tighten the driving V belts 90. The movable take-up pulley 86 is then adjusted to tighten the conveyor belt 42 to the `desired degree of tension. By this arrangement the conveyor belt 42 is normally driven at a speed of about three hundred fty feet per minute but the speed may be increased to as much as five hundred fifty feet per minute when greater production is required, as previously explained.

From the driving pulley 87, the belt 42 continues rear- Wardly in flat condition over additional idler rollers 84 until it reaches the region of the conveyor pivot 31 where it passes beneath a guide roller 96 and extends horizontally beneath the two wheel axles 21 to a tail pulley 97 that is rotatably mounted on the rear lower cross frame member 16 of the vehicle frame 10. As best shown in FIGS. 1, 2 and 4, the conveyor pivot is disposed at the rear end of the lower horizontal side frame members which terminate in front of the rear wheel bogie 11. From the end of each side frame member 15, an arched frame extension 101 reaches upwardly and rearwardly over the bogie 11 and down to the rear cross frame member 16. The raised frame extension 101 provides clearance for operation of the bogie 11 that carries the rear wheels 22 and in order to save space the return run of the belt 42 is passed beneath the bogie axles 21.

From the tail pulley 97, the upper or load carrying run of the belt 42 extends forwardly in flat condition and passes beneath a guiding roller 103 at the rear edge of the aggregate batcher 25. The guiding roller 103 is protected by a transverse gate or shield 104 that extends from the belt 42 upward just in front of the roller in position to prevent aggregates discharged from the batcher 25 vfrom striking the roller 103. As the belt 42 passes forward in the loading area beneath the aggregate batcher .25 it is supported upon a series of closely spaced, nearly horizontal troughing rollers 105. The rollers 105 trough the belt only slightly for receiving the batches of aggregates from the batcher 25 and are arranged sufficiently close together to resist the impact of the falling aggregates as they strike the belt.

From the aggregate batcher loading zone, the belt 42 carries the batched aggregates forward over the troughing rollers 79 that trough the belt more deeply as it enters the blending box 48 which is best shown in FIG. 6. As previously mentioned, within the blending box 48 each side of the conveyor is provided with a skirt plate 49 that depends from a top plate 108 and that engages the carrying surface of the belt 42 near its outer edge to prevent the escape of materials from the belt and to confine dust that may arise from them. These skirt plates 49 extend rearwardly from the blending box to the transverse shield 104 at the rear of the aggregate batcher 25 thereby forming an enclosed loading area.

As may best be seen in FIGS. 5 and 6, the top plate 108 of the blender box 48 is provided with a central open- -ing 109 through which the cement batcher 27 discharges the batches of dry cement on to the conveyor 30. By opening the cement batcher discharge gate 47 gradually, each batch of cement is distributed over the surface of the corresponding batch of aggregates as the troughed belt 42 moves forward through the blending box 48. The cement flowing through the opening 109 tends to spread more or less evenly over the underlying aggregates and is prevented from overiiowing the upturned sides of the belt by the confining skirt plates 49. Any dust that arises from the down-flowing cement likewise is confined within the blender box 48 and settled back on to the loaded belt 42.

As the loaded upper run of the belt 42 passes forward out of the blender box 48, it travels beneath a protective cover 111 that may be of canvas or the like and that is carried by the side frame members '70 of the conveyor 30. As best shown in FIG. 2, the canvas cover 111 extends along the top of the conveyor 30 all the way from the `blending box 48 to the charging chute 82 at the head end of the conveyor. The cover 111 serves to prevent the cement from being blown from the conveyor by the wind and otherwise protects the conveyor from the weather as well as connes dust.

As best shown in FIG. 2, the lower end of the charging chute 82 depending from the head of the conveyor is provided with a water ring 112 of the usual construction whereby water may be introduced into a truck mixer hopper H, for example, along the stream of cement and aggregates being charged into it from the conveyor 30. Water is supplied to the water ring 112 by means of the usual water pump and meter arrangement (not shown) whereby the proper quantity of water ows into the periphery of the stream of batched aggregates and cement as these ingredients are being charged into the hopper H of the mixer. The Water may carry with it the usualadditives that are introduced into it automatically in the proper proportions. Beneath the water ring 112, a depending rubber tube 113 serves to guide the batched ingre-dients into the charging hopper H.

The conveyor belt driving motor 92 is preferably an electric motor of the usual type and it is provided with electrical energy from a power control panel 115 that is mounted on the left side of the forwardly projecting goose neck 12 at the front of the vehicle frame 10 as shown in FIG. 2. The power control panel 115 is provided with the usual power controlling and protective electrical control apparatus, motor starters and the like (not shown) that distribute and control the electrical power for the belt driving motor 92 and for the other electric motors, lights, etc., required in connection with the operation of the hatching plant. This includes the motor that drives the pump (not shown) of the hydraulic pressure supply unit 67, the motor that drives an air compressor 116 mounted on the frame 10 behind the aggregate batcher 25, the motor that drives the aeration blower (not shown) `and the motor for driving the water pump (not shown).

The air compressor 116 stores air under pressure in a tank 117 mounted in the frame 10 at the right side of the vehicle beneath the aggregate bin 26. Air under pressure from the tank 117 is used to operate the automatic charging gates and discharging gates associated with the aggregate batcher 25 and the cement batcher 27 as well as for other purposes. Although the control apparatus for the various electric motors is mounted in the power panel 115, the push buttom switches for starting and stopping the motors are preferably mounted for convenience on the batch control panel 40.

Electrical power for operating the hatching plant is ordinarily obtained from a nearby electrical power transmission line that is connected to the power control panel 115 in the usual manner. If a transmission line is not available near the site of the operation, however, a small portable engine driven electrical generator may be utilized to furnish the required electrical energy.

When a construction project is completed and it becomes necessary to move the mobile hatching plant to another site of operation, the belt conveyor structure 30 -is unlocked from the upper part'78 of the frame extension 75 by withdrawing the locking pins 77. The hydraulic actuators 73 are then operated from the hydraulic supply unit 67 to lower the conveyor 30 until it rests upon the cross member 76 of the frame extension 75 in its travelling position as shown in FIGURE 1 with its charging chute 82 just below the level of the top of the vehicle frame 10. The quick clamp connection 51 between the cement bin 28 and the cement batcher 27 is then disconnected and the cement bin hydraulic actuator 63 is extended and connected to the cement bin lug 64. Hydraulic pressure is then supplied to the actuator 63 to sustain the weight of the bin 28 whereupon the bin locking pins 59 are removed. The control valves on the hydraulic supply unit 67 are then manipulated to cause the cement bin 28 to pivot forward and downward in a gradual manner between the upper side frame members 18 as previously explained into the space within the frame 10 that was vacated by the conveyor 30 when it was moved down to travelling position. In doing so the cement bin will depress part of the canvas cover 111 and some of the troughing rollers in that region may be of the folding type to permit flattening of the belt 42. The cement bin 28 then assumes its horizontal travelling position with the abutment strips 61 on the respective sides of the bin engaging the tops of the side frame members 18 as shown in FIGURE 1.

After the conveyor and the cement bin have been lowered, the electrical power supply wires are disconnected from the control panel, the batchers and scales then are locked and secured in travelling position and the plant otherwise made ready for transportation of the entire apparatus as a single unit along the highway. The

towingtractor T is backed into position beneath the forwardly' extending head end of the conveyor 30 as shown in FIGURE 1 and hitched to the fifth wheel 13 of the goose-neck 12. The blocks B are then removed from beneath the side frame members 15 whereupon the entire folded hatching plant may be moved out as a single semitrailer unit and'driven over public highways to a new site of operations.

From the foregoing description of an exemplifying mobile concrete hatching plant embodying the self-erecting features of the present invention together with the explanation of the manner in which the plant is moved about and prepared for operation, it is apparent that a new and novel integral unithas beenprovided that overcomes the difficulties encountered heretofore in connection with previously used portable plants and -that provides a mobile hatching plant having large capacity for receiving and apportioning the ingredients of concrete in order to effect major batching'operations, the entire plant being mounted on a single transportation vehicle of dimensions appropriate for travelling on public highways. j 'f This new and improved result is achievedl by means of the described novel hatching plant that includes a cement bin of substantial capacity which folds into the frame of the vehicle for transportation and a compartmented aggergate bin that can be filled expeditiously from nearby storage piles. The cement bin is arranged to be raised by power to its operating position and the mobile plant includes all of the equipment necessary to effect substantial hatching operations comparable to the operations of large stationary hatching plants.

Although a specic example of a typical improved mobile concrete hatching plant has been set forth in detail by way of a full disclosure of a practical working embodiment of the persent invention, it is to be understood that new features of the hatching plant herein disclosed may be utilized in connection with other hatching plants or similar equipment and in somewhat different structural forms by those familiar with the hatching art without departing from the spirit and scope of the invention as defined in the subjoined claims.

The novel features of this invention having been fully set forth and explained herein, we claim as our invention:

1. A mobile hatching plant for receiving, weighing, and blending the ingredients of concrete and delivering the same in pre-selected quantities comprising a frame including spaced upper and lower longitudinal members, said frame .having rear transverse axles provided with ground engaging wheels and having forwardly a fth wheel bracket adapted for attachment to a tractor and towing of the plant as a semitrailer, an endless belt conveyor having a lower loading section between the lower members of said frame at the rear thereof and an inclined section projecting forwardly from said frame over said fifth wheel bracket and having an elevated discharge end at the forward end of the plant, said conveyor including a lower tail pulley carried by said frame rearwardly of said axles and an endless belt having upper and lower runs supported respectively above and below said axles, aggregate weigh hoppers supported by said frame immediately over said belt conveyor loading section at the rear of the plant, aggregate receiving bins supported within and reinforcingly connecting the upper frame members over said weigh hoppers, a cement weigh hopper supported by said frame over the belt conveyor loading section at approximately the center of the frame, and a cement receiving bin having pivotal support connections to said frame near said cement weigh hopper, said bin having means engageable with said frame members for its support in a lower position immediately above said belt conveyor and means for pivoting the hin to and securing the same in an upright operative position above said cement weigh hopper.

2. The combination of claim 1 wherein said inclined section is pivotally connected to said frame forwardly of said axles and rearwardly of said hopper and said plant includes means for lowering said section from its operative position to a transport position prior to moving and to allow lowering of said cement bin into the space occupied hy the inclined section of the conveyor when in the operative position.

3. The combination of claim 1 wherein the plant further includes a water measuring system carried by the frame and having fittings for connection to a water supply and a discharge associated with the discharge end of the conveyor and automatic scale means for -cyclically controlling the discharge of the bins and hoppers and water system.

4. In a mobile cement hatching plant, a highway vehicle including an open frame, running gear supporting said frame in manner to constitute therewith a vehicle adapted for operating along a highway, a movable cement bin of large capacity adapted to repose longitudinally substantially fully within said open frame when in travelling position therein the discharge end of said bin presenting an offset discharge opening of reduced size lying at the upper edge of said frame, trunnions carried by said cement bin in the region of said offset discharge opening, bearings in the upper sides of said frame in position to receive and journal said trunnions on said -cement bin respectively, hatching equipment carried in said frame beneath said offset discharge opening of said cement hin, and power actuated means mounted in said frame and operatively connected to said cement bin in manner to pivot said bin upwardly about said trunnion bearings to an upright operating position above said frame with said discharge opening remaining in elevated position for discharging cement by gravity into said hatching equipment.

5. In a mobile hatching plant for apportioning the ingredients of concrete, a vehicle frame of open truss type, running gear supporting said truss type frame in manner to constitute therewith a vehicle appropriate for travelling on public highways, an ingredient conveyor extending longitudinally with said truss frame along the bottom thereof in manner to project outwardly and upwardly heyond one end of said frame, means movably mounting said conveyor in said frame in manner to provide for raising the outwardly and upwardly projecting end thereof to an elevated discharging position, an aggregate bin mounted in said truss frame in position to supply batches of aggregates to said conveyor, a movable cement bin mounted in said truss frame, means to raise said movable cement bin to an elevated position in said frame adapted to supply batches of cement to said conveyor for movement thereon with the batches of aggregates to the elevated projecting discharge end thereof, means to lower said movably mounted conveyor within said truss frame to travelling position along the bottom thereof, and means to lower said movable cement bin substantially fully within said truss frame to travelling position above said lowered conveyor, thereby to adapt said mobile hatching plant for movement as a unitary vehicle along public highways.

6. In a unitary mobile hatching plant for hatching the ingredients of concrete or the like, a box-like vehicle frame of dimensions appropriate for operation over a highway, road wheels arranged to support the rear of said frame, a goose-neck hitch at the forward end of said frame for connection to a towing tractor, a belt conveyor extending longitudinally of said box frame along the bottom thereof at the rear and thence forwardly and upwardly to project beyond the forward end of said frame at an elevation to 4clear a towing tractor and to provide for discharging hatched ingredients into a hauling vehicle, an aggregate batcher supported within the rear of said frame in position to discharge hatched aggregates upon said belt conveyor, a cement batcher supported within said frame forwardly of said aggregate batcher in position to discharge hatched cement onto said belt conveyor,

and a cement bin pivotally mounted within said ybox-like frame above said cement batcher, the arrangement being such that when said cement bin is pivoted to vertical position it is disposed to discharge cement into said cement batcher, said cement bin being so shaped that when it is pivoted to horizontal position in the forward direction it ts down into said box-like frame above said upwardly and forwardly extending belt conveyor thereby to adapt said unitary portable batching plant for operation as an integral vehicle over a highway.

7. In a mobile cement batching plant, an open boxtype vehicle frame including spaced parallel upper and lower longitudinal frame side members, running gear supporting said box frame in manner to constitute therewith a vehicle adapted for travel on highways, a cement bin shaped to fit longitudinally between said parallel frame members and substantially wholly within the box frame when disposed horizontally in travelling position in said frame, longitudinally extending abutment members along the upper portion of said cement bin and extending longitudinally of and engaging the upper edge of said box frame to support said bin along the upper edge of said 16 frame with its upper surface substantially flush with said upper longitudinal frame members, pivot bearing mem-l bers pivotally connecting one end of said cement bin to said upper longitudinal frame members in such manner that said cement bin may be pivoted thereon upwardly from its horizontal travelling position to a vertical operat ing position, means to lock said bin to said upper longitudinal frame members when in the vertical operating position, and a cement batcher mounted in said frame in position to receive and batch cement owing by gravity from said bin when said bin is in vertical operating position. i

References Cited by the Examiner UNITED STATES PATENTS 1,705,336 3/1929 Pape 214-10 3,189,327 6/1965 Domenighetti 259--154 3,198,494 8/1965 Curran et al. 259-154 3,251,484 5/1966 `Hagan 214-2 MARVIN A. CHAMPION, Primary Examiner. 

7. IN A MOBILE CEMENT BATCHING PLANT, AN OPEN BOXTYPE VEHICLE FRAME INCLUDING SPACED PARALLEL UPPER AND LOWER LONGITUDINAL FRAME SIDE MEMBERS, RUNNING GEAR SUPPORTING SAID BOX FRAME IN MANNER TO CONSTITUTE THEREWITH A VEHICLE ADAPTED FOR TRAVEL ON HIGHWAYS, A CEMENT BIN SHAPED TO FIT LONGITUDINALLY BETWEEN SAID PARALLEL FRAME MEMBERS AND SUBSTANTIALLY WHOLLY WITHIN THE BOX FRAME WHEN DISPOSED HORIZONTALLY IN TRAVELLING POSITION IN SAID FRAME, LONGITUDINALLY EXTENDING ABUTMENT MEMBERS ALONG THE UPPER PORTION OF SAID CEMENT BIN AND EXTENDING LONGITUDINALLY OF AND ENGAGING THE UPPER EDGE OF SAID BOX FRAME TO SUPPORT SAID BIN ALONG THE UPPER EDGE OF SAID FRAME WITH ITS UPPER SURFACE SUBSTANTIALLY FLUSH WITH SAID UPPER LONGITUDINAL FRAME MEMBERS, PIVOT BEARING MEMBERS PIVOTALLY CONNECTING ONE END OF SAID CEMENT BIN TO SAID UPPER LONGITUDINAL FRAME MEMBERS IN SUCH MANNER THAT SAID CEMENT BIN MAY BE PIVOTED THEREON UPWARDLY FROM ITS HORIZONTAL TRAVELLING POSITION TO A VERTICAL OPERATING POSITION, MEANS TO LOCK SAID BIN TO SAID UPPER LONGITUDINAL FRAME MEMBERS WHEN IN THE VERTICAL OPERATING POSITION, AND A CEMENT BATCHER MOUNTED IN SAID FRAME IN POSITION TO RECEIVE AND BATCH CEMENT FLOWING BY GRAVITY FROM SAID BIN WHEN SAID BIN IS IN VERTICAL OPERATING POSITION. 